Rename ffmpeg-4.2-fit to ffmpeg-4-fit

trunk/3rdparty/ffmpeg-4-fit/libavutil/spherical.c

@@ -0,0 +1,79 @@
+/*
+ * Copyright (c) 2016 Vittorio Giovara <vittorio.giovara@gmail.com>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "mem.h"
+#include "spherical.h"
+
+AVSphericalMapping *av_spherical_alloc(size_t *size)
+{
+    AVSphericalMapping *spherical = av_mallocz(sizeof(AVSphericalMapping));
+    if (!spherical)
+        return NULL;
+
+    if (size)
+        *size = sizeof(*spherical);
+
+    return spherical;
+}
+
+void av_spherical_tile_bounds(const AVSphericalMapping *map,
+                              size_t width, size_t height,
+                              size_t *left, size_t *top,
+                              size_t *right, size_t *bottom)
+{
+    /* conversion from 0.32 coordinates to pixels */
+    uint64_t orig_width  = (uint64_t) width  * UINT32_MAX /
+                           (UINT32_MAX - map->bound_right  - map->bound_left);
+    uint64_t orig_height = (uint64_t) height * UINT32_MAX /
+                           (UINT32_MAX - map->bound_bottom - map->bound_top);
+
+    /* add a (UINT32_MAX - 1) to round up integer division */
+    *left   = (orig_width  * map->bound_left + UINT32_MAX - 1) / UINT32_MAX;
+    *top    = (orig_height * map->bound_top  + UINT32_MAX - 1) / UINT32_MAX;
+    *right  = orig_width  - width  - *left;
+    *bottom = orig_height - height - *top;
+}
+
+static const char *spherical_projection_names[] = {
+    [AV_SPHERICAL_EQUIRECTANGULAR]      = "equirectangular",
+    [AV_SPHERICAL_CUBEMAP]              = "cubemap",
+    [AV_SPHERICAL_EQUIRECTANGULAR_TILE] = "tiled equirectangular",
+};
+
+const char *av_spherical_projection_name(enum AVSphericalProjection projection)
+{
+    if ((unsigned)projection >= FF_ARRAY_ELEMS(spherical_projection_names))
+        return "unknown";
+
+    return spherical_projection_names[projection];
+}
+
+int av_spherical_from_name(const char *name)
+{
+    int i;
+
+    for (i = 0; i < FF_ARRAY_ELEMS(spherical_projection_names); i++) {
+        size_t len = strlen(spherical_projection_names[i]);
+        if (!strncmp(spherical_projection_names[i], name, len))
+            return i;
+    }
+
+    return -1;
+}